The Pennsylvania departments of Health and Agriculture are warning people who bought raw milk and raw milk cheese from Stump Acres Dairy in New Salem to throw it out immediately because of the risk of listeria monocytogenes contamination.
Officials said raw milk collected during an April 24 investigation of the farm tested positive for the bacteria. The testing process for listeria can take up to 10 days.
Pennsylvania law allows farms to sell raw milk, which is milk that has not been pasteurized, but requires the farms to have a permit and be inspected by the Agriculture Department to reduce health risks.
The Agriculture Department revoked Stump Acres' permit in 2007 after several people become sick after drinking raw milk from the dairy. The farm, at 1737 Arnold Road in North Codorus Township, currently does not have a permit, officials said.
Health Department officials said they are not aware of any illnesses related to the products.
The officials said symptoms of listeriosis usually appear within one-to-three weeks, but can occur as short as three days or as long as 70 days after consumption and include fever, muscle aches and gastrointestinal symptoms such as nausea or diarrhea.
If the infection spreads to the nervous system, symptoms such as headache, stiff neck, confusion, loss of balance or convulsions can occur.
Infected pregnant women may experience only a mild, flu-like illness, but infections during pregnancy can lead to miscarriage or stillbirth.
Anyone who consumed a product from Stump Acres Dairy and has symptoms should consult their physician, visit their local state health center, or call 877-PA HEALTH (724-3258).